Inulin is a prebiotic so it is good for you. You can buy it at places like Vitacost or iherb. Start with a tiny amount for a few days and build up slowly or it can cause gas and bloating, though it will do no real harm. it works!
I am not sure with this inulin because I have not tried it yet. I am also afraid of the side effects it may bring to our body. If I were you, you will have to take what I have been taking if I have my constipation. I have this Digestic which was prescribed to me by my doctor when I was suffering chronic constipation. It is very effective for me and I can say it is my best reliever in constipation problem.